1. Field of Invention
The present invention relates generally to a welding torch assembly. More particularly, the present invention relates to an improved liquid-cooled welding torch assembly for use in robotic welding.
2. Prior Developments
Robotic welding torches are used in arc welding environments requiring repetitious precision welding, such as mass production of automobiles or automotive parts. Arc welding robots are generally high precision, computer controlled machines containing electric servomotor drives. The welding robots use special interfaces to connect with robotic arc welding equipment. The welding robots typically use an articulating jointed arm to move the attached robotic torch assembly to the desired position. Robotic welding is often used for arc welding parts where the production volume and complexity are large. Robotic torches, such as robotic metal inert gas (MIG) torches, utilize consumable wire electrodes fed from a spool in a separate wire feeder. Also, the robotic torches require a supply of shielding gas and electric current to perform the welding tasks.
The rapid and precise welding applications for which robotic MIG welding torches are used require torch assemblies that are easily assembled and repaired. Robotic welding devices may be subject to heat and wear due to continuous operation. Also, accidental collisions between the welding torch and the workpiece being welded can damage the welding torch. Accordingly, it may be necessary to replace one or more parts of the welding torch during its use. However, since liquid-cooled welding torches employ liquid coolant lines, it is necessary that an adequate seal be maintained when the components are reconnected. It is also necessary for coolant to be retained within the coolant system when a liquid-cooled welding torch is disconnected. Liquid-cooled welding torches with removable components typically use seals that are prone to damage and subsequent leakage every time a welding torch is disassembled and reassembled. Furthermore, realignment of the welding torch after replacing one or more components is important so that the welding tip is always where the robot expects it to be during operation.